<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .car {
            background-color: #ff0;
            width: 50px;
            height: 50px;
        }
    
        .number {
            background-color: #f00;
            position: absolute;
            top: -5px;
            right: 0;
        }
    
        .buy-car {
            background-color: #0f0;
            width: 70px;
            height: 70px;
            position: relative;
            margin: 100px;
        }
    </style>
</head>
<body>
    <div class="buy-car">
        <div class="car">车子</div>
        <div class="number">数字</div>
    </div>
</body>
</html>